Statistics and Probability Answers

The finished inside the diameter of a piston ring is normally distributed with a mean of 10 cm and a standard deviation of 0.03 cm.

a) what proportion of rings will have inside diameters exceeding 10.075 cm?

b) what is the probability that a piston ring will have an inside diameter between 9.97 and 10.03 cm?

c) below what value of inside diameter will 15% of the piston rings fall?

Solve the given problem. Dont forget to show your solutions.

1.AA pop fourulstion consist of the four numbers 1,2,4 and 5. List all the possible samples of sizes n=3 wich can be drawn with replacement from the population. Find the following : a. Population mean b. Population variance c. Population standard deviation d. Mean of the sampling distribution of sample means e. Variance of the sampling distribution of sample means f standard deviation of the sampling distribution of sample means

Show your solution:

1. If the population of ABM students of Malaya Integrated High School has a mean of 12.45, what

is the mean of the sampling distribution of its mean?

2. If the mean of the sampling distribution is 24.29, what is the mean of the population?

3. If a population of HUMS students of Makabayan National High School has a variance of 6.4,

what is the variance of the sampling distribution of the sample mean if the sample size is 4 and all

the possible samples are drawn with replacements?

4. If the population of STEM students of Siyensiya Stand Alone Senior High School has a standard

deviation of 9.4, what is the standard deviation of the sampling distribution of its means? The

sampling distribution was derived with sample size n=3, and all the possible samples were drawn

with replacements.

5. If the population standard deviation is 5.6, what is the population variance

Suppose a random variable  x is best described by a normal distribution with  μ = 60 and   Find the  z-score that corresponds to the value  x = 63.

Suppose a random variable x is best described by a normal distribution with μ = 60 and Find the z-score that corresponds to the value x = 63.

Let us consider two sections: section 1 contains 7 male and 10 female students, and section 2 contains 9 male and 7 female students. One section is selected at random and then one student is selected from this section. Find the probability that the selected student is male.

Given the following data on the ages of 75 persons in years. Calculate the first four central moments. Age 09.5–14.5 ,14.5–19.5 , 19.5–24.5 , 24.5–29.5 , 29.5–34.5 ,34.5–39.5, 39.5–44.5 , 44.5–49.5

Number of persons: 3,6,8,12,8,6,3,2 Total 75

Full details explain

Calculate the standard deviation and CV for the age distribution presented below:

Age: 09.5-12.5 12.5-15.5 15.5-18.5 18.5-21.5 21.5-24.5 24.5-27.5 27.5-30.5

Frequency: 3 14 23 12 8 4 1

Explain your results

A company sends a random sample of 16 of its sales- people to a course designed to increase their moti- vation and, hence, presumably their effectiveness. In the following year these people generated sales with an average value of $625,000 and a sample stan- dard deviation of $80,000. During the same period, an independently chosen random sample of 10 sales- people who had not attended the course obtained sales with an average value of $608,000 and a sample standard deviation of $73,000. Assume that the two population distributions are normal and have the same variance. Find a 90% confidence interval esti- mate for the difference between the population mean sales for salespeople who attended the motivational course and for those salespeople who did not attend the course.

 A newspaper article reported that 350 people in one state were surveyed and 60% were opposed to a recent court decision. The same article reported that a similar survey of 550 people in another state indicated oppo- sition by only 20%. Construct a 95% confidence inter- val of the difference in population proportions based on the data.